Larix lyallii and L . occidentalis ( Larix sect. Multiseriales ) are similar morphologically and have similar geographic ranges. Just how closely the two species are related has not been determined, but they probably originated from a common ancestor resembling L . potaninii Batalin. Although the geographic ranges of the two species overlap considerably, elevational differences of 150 to 300m usually separate them. Some morphologically intermediate specimens have been collected from Washington and Montana.

Because of its restricted distribution and growth at timberline, alpine larch has no commercial importance; it is often dwarfed and misshapen.